With advances in quartz watch technology, there has been great improvement in the timekeeping accuracy of watches. However, in striving to attain accurate timekeeping, it is necessary to impart external correction to a quartz watch at some interval.
A type of watch having a radio-signal correction function, a receiving function being added to the watch so as to use a radio or TV time broadcast as a means for correcting the time, has already been adopted for use as facilities watches and in VCRs. In addition, there are longwave standards signals which include time/calendar information in the form of a modulated time code, these being widely used in Europe.
By using this radio signal having a time code, it is not necessary, as it is with a radio-signal correction function watch which uses the information from a radio or TV broadcast, to set the time beforehand, so that even if the time on the watch is incorrect, after radio signal correction is completed, the correct time is accurately captured by the watch.
Thus, a watch having a receiving function which receives a radio signal having a time code not only keeps time accurately, but also does not require the setting of time, making it extremely easy to use.
As watches having a radio-signal correction function gained market acceptance, there has been a desire to have watches with such functions as a local time function, an alarm function, and a chronograph function, which previous multifunction watches had. Because of this desire, the applicant developed a watch with a radio-signal correction function such as set forth in the Japanese Patent Application No. 7-11650.
A previous watch with a radio-signal correction function is described below, with reference being made to relevant drawings.
FIG. 4 is a block diagram of a watch 200 with a radio-signal correction function having a local time function. In this block diagram, the reference numeral 1 denotes an oscillator circuit, which is an oscillation means, 2 is a frequency division circuit which divides the oscillation signal S1 that is output from the oscillator circuit 1, this frequency division circuit thereby generating the frequency-divided signal S2 which is required for the timekeeping of hour/minutes and seconds, and the frequency-divided signal S3 which is required for drive of the minute hand every minute and drive of the second hand every second.
The frequency division circuit 2 has a reset function, and when the reset signal S28 is high, it goes into the reset condition, the minute dividing operation being thereby stopped. The reference numeral 31 denotes a hour/minute drive pulse generating circuit which generates an hour/minute drive pulse S4 from the frequency-divided signal S3 and which, when a non-coincidence signal S5 from an hour/minute position determining circuit is at the high level, continuously outputs the hour/minute drive pulse S4. 32 is an hour/minute counter which performs timekeeping of hours and minutes by counting the frequency-divided signal S2, which can count up by one minute at the rising edge of an hour/minute correction signal S21 from a correction contents selecting means 11 to be described later, and which also corrects the time data in accordance with a time data signal S32 from a time code generating circuit 143.
The hour/minute counter 32 outputs an hour/minute count data signal S6 as time data, and when the time data reaches a priorly established time, this hour/minute counter 32 outputs a scheduled receiving operation signal S23 in high level.
After a certain amount of time has elapsed, or when the time data signal S23 is input, the receiving operation signal S23 is made low level. The reference numeral 33 denotes a time-difference counter, which generates time-difference data using as a reference the time data from the counting data signal S6 of the hour/minute counter 32 and outputs a local time counting data signal S7.
The time-difference data of the time-difference counter 33 is counted up by 1 hour in accordance with the rising edge of a time-difference correction establishing signal S22 from the correction content selecting means 11, which will be described later. The reference numeral 134 denotes an hour/minute hand position determining circuit, which has within it a hand position counter that is linked to the hour/minute hand 36.
When a home time display signal S15 from a switch means 7 to be described later is at the high level, this hour/minute hand position determining circuit 134 makes a coincidence comparison between the hour/minute count data S6 from the hour/minute counter 32 and an internal hand position counter, and if there is non-coincidence between the two, it outputs a non-coincidence signal S5 as a high level.
When the local time display signal S16 from the switch means 7 to be described later is at a high level, the hour/minute hand position determining circuit 134 performs a coincidence comparison between the time-difference count data signal S7 from the time-difference counter 33 and the internal hand position counter, and if there is non-coincidence, it outputs the non-coincidence signal S5 as a high level.
Additionally, when the reference hand position display signal S17 from the switch means 7 is at a high level, the hour/minute hand position determining circuit 134 performs a coincidence comparison between the reference hand position data signal (not shown in the drawing) and the internal hand position counter, and if there is non-coincidence, it outputs the non-coincidence signal S5 as a high level.
The hour/minute drive pulse generating circuit 31, the hour/minute counter 32, the time-difference counter 33, and the hour/minute hand position determining circuit 134 make up the timekeeping means 103. The reference numeral 35 denotes an hour/minute motor which is driven in accordance with the hour/minute drive pulse S4 from the hour/minute drive pulse generating circuit 31, this motor driving the hour/minute hand 36. The hour/minute motor 35 and hour/minute hand 36 make up the display means 4.
The reference numeral 51 is a second drive pulse generating circuit which generates a second pulse drive pulse S11 from the frequency-divided signal S3, and which, when the non-coincidence signal S13 from the second hand position determining circuit is at high level, continuously outputs the second pulse drive pulse S11.
52 is a second counter which performs timekeeping each second by counting the frequency-divided signal S2, and which also clears the time data to zero in accordance with the time data signal S32 from a time code generating circuit 143. The second counter 52 outputs time data as a second count data signal S12.
The reference numeral 153 is a second hand position determining circuit which has an internal second hand position counter (not shown in the drawing) that is linked to the second hand 55.
When the receiving enable signal S42 from the receiving enabling means 12 is at a low level, the second hand position determining circuit 153 performs a coincidence comparison between the second count data S12 from the second counter 52 and the hand position counter, and if there is non-coincidence, it outputs the non-coincidence signal S13 at a high level.
If the receiving enable signal S42 is at a high level, the second hand position determining circuit 153 performs a coincidence comparison between the receiving condition indication position data signal (not shown in the drawing) and the hand position counter, and if there is non-coincidence it outputs the non-coincidence signal S13 at a high level.
Additionally, when the reference hand position display signal S17 from the switch means 7 is at a high level, the second hand position determining circuit 153 performs a coincidence comparison between the second hand reference position data signal (not shown in the drawing) and the hand position counter, and if there is non-coincidence, it outputs the non-coincidence signal S13 at a high level.
The second drive pulse generating circuit 51, the second counter 52, and the second hand position determining circuit 153 make up the timekeeping means 105. The reference numeral 54 denotes a second motor which is driven by a second drive pulse S11 from the second drive pulse generating circuit 51, this motor driving the second hand 55.
The reference numeral 7 is a switch means which is made up of the switches 71a, 72a, and 73a, one of which when in the ON condition is connected to the VDD level (high level), the switches 74a and 75a which are connected to the VDD level (high level) when in the ON condition, and the pull-down resistors 71b, 72b, 73b, 74b, and 75b which are connected to the VSS level (low level).
71a is a home time display switch (hereinafter referred to as the HT switch) which in the ON condition make the home time display signal S15 a high level (VDD level), and which in the OFF condition makes the home time display signal S15 a low level (VSS level), via the pull-down resistor 71b.
72a is a local time display switch (hereinafter referred to as the LT switch) which in the ON condition makes the local time display signal S16 a high level (VDD level), and which in the OFF condition makes the local time display signal S16 at a low level (VSS level), via the pull-down resistor 72b.
73a is a reference hand position display switch (hereinafter referred to as the KT switch) which in the ON condition makes the reference hand position display signal S17 a high level (VDD level) and which in the OFF condition makes the reference hand position display signal S17 a low level (VSS level), via the pull-down resistor 73b.
71a, 72a, and 73a form the rotary switch 71. 74a is a correction status setting switch (hereinafter referred to as the SJ switch) which in the ON condition makes the correction selection signal S18 a high level (VDD level) and which in the OFF condition makes the correction selection signal S18 a low level (VSS level) via the pull-down resistor 74b.
75a is a correction switch which in the ON condition makes the correction signal S19 a high level (VDD level) and which in the OFF condition makes the correction signal a low level (VSS level), via the pull-down resistor 75b.
The reference numeral 11a denotes an AND gate which, when the correction selection signal S18 from the SJ switch 74a is a high level, outputs the correction signal S19 from the correction switch 75a as the correction signal S20. 11b is an AND gate which, when the home time display signal S15 from the HT switch 71a is a high level, outputs the correction signal S20 from the AND gate 11a as the hour/minute correction signal S21.
11c is an AND gate which, when the local time display signal S16 from the LT switch 72a is a high level, outputs the correction signal S20 at the time-difference correction signal S22. The AND gates 11a, 11b, and 11c form the correction contents selection means 11.
The reference numeral 12 is an AND gate which is a receiving enable means, and when the home time display signal S15 from the HT switch 71a is a high level, this AND gate outputs the scheduled receiving operation signal S23 from the hour/minute counter 32 as the receiving enable signal S42. 41 is an antenna which receives a radio signal having a time code, this generating a radio signal S30.
42 is a receiving circuit which demodulates the radio signal S30, thereby generating the demodulated signal S31. 143 is a time code generating circuit which generates a time code from the demodulated signal S31, and which supplies the time data signal S32 to the hour/minute counter 32 and second counter 52 at the timing of the beginning of a minute. The antenna 41, the receiving circuit 42, and the time code generating circuit 143 form the time code receiving means 113, this time code receiving means operating when the receiving enable signal S42 from the receiving enabling means 12 is a high level.
The operation of a watch 200 with a radio-signal correction function configured as described above will be described with reference to FIG. 4 and FIG. 5. FIG. 5 is an outer view of a watch of the past which had a radio-signal correction function. When the HT switch is in the ON condition, because the home time display signal S15 is at a high level, the hour/minute hand position determining circuit 134 performs a coincidence comparison between the hour/minute count data signal S6 from the hour/minute counter 32 and the internal hand position counter.
For example, if the frequency-divided signal S2, which is a pulse of every second, is counted for 20 seconds and the hour/minute counter 32 advances the hour/minute data by 1, because there is non-coincidence between the hour/minute count data S6 of the hour/minute counter 32 and the hand position counter, the hour/minute hand position determining circuit 134 outputs the non-coincidence signal S5 at a high level.
Therefore, the hour/minute drive pulse generating circuit 31 outputs the hour/minute drive pulse S4. The hour/minute drive pulse S4 drives the hour/minute motor 35 of the display means 4 by one pulse, and the hour/minute hand position determining circuit 134 increments the hand position counter by 1 count, thereby causing coincidence with the hour/minute count data S6, so that the non-coincidence signal S5 is changed to a low level, thereby prohibiting the next hour/minute drive pulse S4 from the hour/minute drive pulse generating circuit 31.
Therefor the hour/minute hand 36 is moved by one step, which is 1/3 of 1 minute, to display the home time. In the same manner, the second hand 55 is moved one step for each second by the second hand position determining circuit 153.
Next, if the user operates the rotary switch 71 which is shown FIG. 4 so that the LT switch 72a is placed in the ON condition, because the local time signal S16 changes to a high level, the hour/minute hand position determining circuit 134 performs a coincidence comparison between the time-difference count data S7 from the time-difference counter 33 and the hand position counter.
The time-difference counter 33 generates time-difference data based on the time data of the hour/minute count data S7 from the hour/minute counter 33 and outputs the local time count data signal S7, and the hour/minute hand position determining circuit 134 outputs the non-coincidence signal S5 as a high level until this local time count data signal S7 coincides with the internal hand position counter. Therefore, the hour/minute drive pulse generating circuit 31 outputs the hour/minute drive pulse S4, thus the motor 35 moves the hour/minute hand 36 to display the local time. When this is done, the second display means 6 operates in the same manner as in the case of home time.
If the user operates the rotary switch 71 so that the KT switch 73a is in the ON condition, because the reference hand position display signal S17 changes to the high level, the hour/minute hand position determining circuit 134 performs a coincidence comparison between the reference hand position data signal and the hand position counter, and outputs the non-coincidence signal S5 at a high level until these coincide.
Therefore, the hour/minute drive pulse generating circuit 31 outputs the hour/minute drive pulse S4, and the hour/minute motor 35 moves the hour/minute hand 36 so as to display the reference hand position. The second hand position determining circuit 153 operates in the same manner, resulting in the second hand 55 displaying the reference hand position.
The second position counter of the reference hand position is at zero, the hand being moved to the reference hand position. In the reference hand position display condition, in addition to verification of whether or not the hand position is correct, because there is no hand movement done, there is little battery consumption, this being effective when storing for long periods of time.
In a watch 200 of the past, when the time reaches a time to which the hour/minute counter is priorly set (for example, 3 AM), the scheduled receiving operation signal S23 is output at a high level. If the HT switch 71a is in the ON condition so that the home time display signal S15 is at a high level, the AND gate 12, which is the receiving enabling means, outputs the scheduled receiving operation signal S23 as the receiving enabling signal S42, thereby placing the time code receiving means 113 in the operating condition.
The time code generating circuit 143 generates a time code from the demodulated signal S31 output from the receiving circuit 42, and when this is completed outputs the time data signal S32 at the timing of the beginning of a minute.
The time data signal S32 corrects the time data of the hour/minute counter 32, and the hour/minute hand 36 of the display means 4 indicates the corrected time data, the second count data of the second hand 52 being cleared to zero, the second hand 55 of the display means 6 being returned to zero. In this manner the watch 200 receives a radio signal with a time code and performs radio signal correction of the time.
When the hour/minute counter 32 reaches 3 AM, the scheduled receiving operation signal S23 is output at high level, and even if in the home time display condition the receiving enabling signal S42 changes to the high level, so that the time code receiving means 113 is place in the operating condition, if the watch 200 with a radio-signal correction function is in a local in which reception of a radio signal having a time code is not possible, it is not possible for the time code generating circuit 43 to output the time-keeping data signal S32, so that when a pre-established amount of time has elapsed (for example 5 minutes), the hour/minute counter 32 returns the scheduled receiving operation signal S23 to the low level, thereby placing the time code receiving means 113 into the non-operating condition, so as to terminate reception.
If at this point rather than the HT switch 71a, either the LT switch 72a or the KT switch 73a is in the ON condition, if the home time display signal S15 is at the low level or the reference hand position display condition is in effect, the AND gate 12, which is the receiving enabling means, outputs the receiving enabling signal S42 at the low level, regardless of the scheduled receiving operation signal S23 from the hour/minute counter 32, thereby prohibiting the operation of the time code receiving means 113. That is, receiving operation is prohibited except when in the home time display condition.
A radio-signal corrected watch 200 of past is used in the home display condition, and when it is possible to receive a radio signal having a time code, keeps extremely accurate time, without the need to set the time. By using the local time display condition, it is possible to use such a watch in areas outside the local time area, such as in an overseas area.
When doing this, the local time is displayed by adding time-difference data to the local time in 1-hour units. With regard to this time-difference data, when the SJ switch 74a of the switch means 7 is in the ON condition so that the correction selection signal S18 is at the high level, if the correction switch 75a is place in the ON condition the correction signal S19 become high level, and the AND gate 11a outputs the correction signal S20 at a high level.
Because the home time display signal S15 is at a low level, the output of the AND gate 11b does not change. However, because the local time display signal S16 from the LT switch 72a of the AND gate 11c is at the high level, the AND gate 11c outputs the correction signal S20 as the time-difference correction signal S22. Therefore, each time the correction switch 75a is placed in the ON condition, the time-difference counter 33 counts up by 1 hour on the rising edge of the time-difference correction signal S22. Thus, in the local time display condition, the hour/minute hand 36 is displayed by adding the time difference to the home time.
A radio signal corrected watch 200 such as described above receives a radio signal having a time code and can not only keep time accurately but also does not require the setting of time, making it extremely easy to use.
This radio signal corrected watch 200 performs receiving operation only when the normally used home time display condition is in effect, and in areas in which a radio signal having a time code does not reach an in overseas areas or the area, even in the home time area, to which no radio signal can be reached, can be used in the local time display condition, with operation of the time code receiving means 113, which has a large operating power consumption, being prevented. Even during long periods of storage and when in the reference hand position display condition for verification of the reference hand position, receiving operation is prohibited, so as to conserve consumption current.
In recent years, environmental issues have been given great importance, and there have been advances made in the adoption of such clean energy policies such as eliminating the replacement and disposal of batteries which are used as electrical power generating means in watches as well, so that such clean energy measures are required in radio signal corrected watches as well.
Practical application of clean energy has been made in the form of mechanical electrical generation and solar cells as electrical generating circuits, these being uses as electrical generating means to charge a charged element such as a secondary cell. If it is not charged for a long period of time, a secondary cell exhibits a voltage drop, so that the watch's functions stop.
Therefore, after topping it is necessary to once again perform electrical generation to charge the cell to a voltage that enables operation of the watch's functions. When doing this, although the watch's functions start, the time information before the watch stopped is lost, so that by imparting an electrical power generating means, it is possible by performing receiving operation to correct the time data after the watch is returned to a voltage enabling operation after being stopped.
However, in radio signal corrected watches in the past, which were multifunctional and had a multiplicity of display conditions, the display condition which enables receiving was limited the home time display condition. The present invention has as an object the elimination of the need for the user to set the time after restoration to a voltage that enables operation after the watch was stopped, regardless of the display condition.